Potential Security Vulnerabilities

[JarLob]

While it is obvious that this is a demo project, it looks maintained and may be used as a template for a real project.

Summary

reactjs-ts-identityserver is vulnerable to Cross-Site Scripting (XSS) and Cross-Site Request Forgery (CSRF) that may lead to the elevation of privileges and per-user denial of service (DoS).

Details

Issue 1: XSS (CVE-2018-0784)

The application doesn't have the fix for CVE-2018-0784 that was found in ASP.NET Core templates. It is vulnerable to XSS if the logged-in user is tricked into clicking a malicious link like https://localhost:44315/manage/EnableAuthenticator?AuthenticatorUri=%22%3E%3C/div%3E%00%00%00%00%00%00%00%3Cscript%3Ealert(%22XSS%22)%3C/script%3E and enters an invalid verification code. Mode details are available in the blog post.

Impact

This issue may lead to the elevation of privileges.

Remediation

Modify the code according to the instructions from the advisory.

Issue 2: CSRF (CVE-2018-0785)

The application doesn't have the fix for CVE-2018-0785 that was found in ASP.NET Core templates. It is vulnerable to CSRF. A logged-in user with enabled Second Factor Authentication (2FA) may lose their recovery codes if they are tricked into clicking a link like https://localhost:44315/manage/GenerateRecoveryCodes or visit a malicious site that makes the request without the user's consent. As a result the user may be permanently locked out of their account after loosing access to their 2FA device, as the initial recovery codes would no longer be valid.

Impact

This issue may lead to the per-user DoS.

Remediation

Modify the code according to the instructions from the advisory.

[ThunderDev1]

Wow, thanks for your detailed issue :)
I will check this out as soon as possible.